Argyle created a market for "champagne" brown diamonds around...

Argyle created a market for "champagne" brown diamonds around 1990 that had previously been used predominantly for industrial uses, it was a highly effective strategy.
They had their first "pink" tender around 1984, there was already a market for high quality fancy coloured diamonds but they did enhance the image.
Yes the market for coloured stones has increased.
Rio's Merlin mining only began around 1998, they basically scooped the easy to get to diamonds and then closed it. They recovered a 105ct D colour stone (broke it during polishing) also several other large Brown, white and Yellow stones. Most of the production is small white/brown diamonds